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Old 09-04-2019, 03:07 PM   #8
RV6A
Seasoned Camper
 
Join Date: Mar 2017
Location: Pine
Posts: 53
M.O.C. #19552
Quote:
Originally Posted by RicTrim View Post
I could have shifted from D to L, but was already at 5K on the tach....

Ric
How fast were you going? On the interstate I travel at 69 mph, this is what 2000 RPM and Overdrive gives me on my 6 speed manual diesel. It is also slightly faster than the Semi's run. Down grades I run 40-45, along with all the Semi's. They creep down for a reason.

My six speed has the following gears. Low, 1, 2, 3, 4 and OD. Granted it is a diesel with a flapper valve in the exhaust (exhaust brake). Gassers have the flapper valve (Butterfly) in the intake so the engine uses compression to brake instead of a potato stuffed in the exhaust.

This weekend I pulled the fiver over the Tunnel and Vail pass, both ways and seldom had to apply brakes. I come down these long steep grades at 40-45 MPH in 3rd with the exhaust flapper closed; engine RPM is around 2600. The higher the RPM the better the exhaust brake works (within reason). This is similar for a gasser. It is important to be in the proper gear and speed before descending, otherwise bad things happen.

Don't let the speed build. If you hit 45, slow down quickly to 40 and allow the brakes time to cool. By all means do not ride the brakes down the hill. Do not get in a hurry.
__________________
Gary Z.
Friends call me Z
2009 3075RL; Modded to our taste.
8500' MSL in Pine, Colorado
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